Go to file
Eric Dumazet 60b1af3300 tcp: reduce skb overhead in selected places
tcp_add_backlog() can use skb_condense() helper to get better
gains and less SKB_TRUESIZE() magic. This only happens when socket
backlog has to be used.

Some attacks involve specially crafted out of order tiny TCP packets,
clogging the ofo queue of (many) sockets.
Then later, expensive collapse happens, trying to copy all these skbs
into single ones.
This unfortunately does not work if each skb has no neighbor in TCP
sequence order.

By using skb_condense() if the skb could not be coalesced to a prior
one, we defeat these kind of threats, potentially saving 4K per skb
(or more, since this is one page fragment).

A typical NAPI driver allocates gro packets with GRO_MAX_HEAD bytes
in skb->head, meaning the copy done by skb_condense() is limited to
about 200 bytes.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25 13:13:31 -05:00
arch net: Remove usage of net_device last_rx member 2017-01-18 17:22:49 -05:00
block
certs
crypto
Documentation net: dsa: mv88e6xxx: Support multiple MDIO busses 2017-01-24 15:33:51 -05:00
drivers mlx5-updates-2017-24-01 2017-01-25 12:49:58 -05:00
firmware
fs Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-01-17 15:19:37 -05:00
include mlx5-updates-2017-24-01 2017-01-25 12:49:58 -05:00
init
ipc
kernel bpf: enable verifier to better track const alu ops 2017-01-24 14:46:06 -05:00
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-01-17 15:19:37 -05:00
mm
net tcp: reduce skb overhead in selected places 2017-01-25 13:13:31 -05:00
samples samples/bpf: add lpm-trie benchmark 2017-01-23 16:10:38 -05:00
scripts
security Introduce a sysctl that modifies the value of PROT_SOCK. 2017-01-24 12:10:51 -05:00
sound
tools bpf: enable verifier to better track const alu ops 2017-01-24 14:46:06 -05:00
usr
virt
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS net: Introduce psample, a new genetlink channel for packet sampling 2017-01-24 13:44:28 -05:00
Makefile Linux 4.10-rc4 2017-01-15 16:21:59 -08:00
README

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.